hypervisor: kvm,qemu

My program use libvirt event , the program is a module(.so) file in cloud application, when unload the module, program will dump in virEventPoolRunOnce call.
program frame

virInitialize
virEventAddTimeOut
virEventRunDefaultImpl
virConnectXXX
virConnectDomainEventRegisterAny
...
virConnectDomainEventDeregisterAny
...

when unload the module will dump , the gdb bt commad output is
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
Core was generated by `/usr/local/lssa/bin/lssa -f'.
Program terminated with signal SIGSEGV, Segmentation fault.
---Type <return> to continue, or q <return> to quit---
#0  0x00007f9a3e9fc2f2 in ?? ()
[Current thread is 1 (Thread 0x7f9a39349700 (LWP 2897))]
(gdb) bt
#0  0x00007f9a3e9fc2f2 in ?? ()
#1  0x00007f9a3e1728bd in virEventPollRunOnce () from /usr/lib/libvirt.so.0
#2  0x00007f9a3e171391 in virEventRunDefaultImpl () from /usr/lib/libvirt.so.0
#3  0x00007f9a3e9fbc16 in ?? ()
#4  0x0000000000000000 in ?? ()
(gdb)

Thanks